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The New York Times just published an article called "The Overflowing American Dinner Plate", in which they describe changes in the American diet since 1970, the period during which the obesity rate doubled. Bill Marsh used USDA estimates of food consumption from 1970 to 2006. Predictably, he focuses on fat consumption, and writes that it has increased by 59% in the same time period. The problem is, we aren't eating any more fat than we were in 1970. The US Centers for Disease Control NHANES surveys show that total fat consumption has remained the same since 1971, and has decreased as a percentage of calories. I've been playing around with the USDA data for months now, and I can tell you that Marsh misinterpreted it in a bad way. Here are the raw data, for anyone who's interested. They're in easy-to-use Excel spreadsheets. I highly recommend poking around them if you're interested.The reason Marsh was confused by the USDA data is that he confused "added fats" with "total fat". While total fat intake has remained stable over this time period, added fats have increased by 59%. The increase is almost exclusively due to industrially processed seed oils (butter and lard have decreased). Total fat has remained the same because we now eat low-fat cuts of meat and low-fat dairy products to make up for it! Another problem with the article is it only shows percent changes in consumption of different foods, rather than absolute amounts. This obscures some really meaningful information. For example, grain consumption is up a whopping 42%. That is the largest single food group change if you exclude the misinterpreted fat data. Corn is up 188%, rice 170%, wheat 21%. But in absolute amounts, the increase in wheat consumption is larger than corn or rice! That's because baseline wheat consumption dwarfed corn and rice. We don't get that information from the data presented in the article, due to the format. So now that I've deconstructed the data, let's see what the three biggest changes in the American diet from 1970 to 2006 actually are:- We're eating more grains, especially white wheat flour
- We're eating more added sweeteners, especially high-fructose corn syrup
- Animal fats from milk and meat have been replaced by processed seed oils
Wheat + sugar + processed vegetable oil = fat and unhealthy. Sounds familiar, doesn't it?
The New York Times just published an article called "The Overflowing American Dinner Plate", in which they describe changes in the American diet since 1970, the period during which the obesity rate doubled. Bill Marsh used USDA estimates of food consumption from 1970 to 2006. Predictably, he focuses on fat consumption, and writes that it has increased by 59% in the same time period. The problem is, we aren't eating any more fat than we were in 1970. The US Centers for Disease Control NHANES surveys show that total fat consumption has remained the same since 1971, and has decreased as a percentage of calories. I've been playing around with the USDA data for months now, and I can tell you that Marsh misinterpreted it in a bad way. Here are the raw data, for anyone who's interested. They're in easy-to-use Excel spreadsheets. I highly recommend poking around them if you're interested.The reason Marsh was confused by the USDA data is that he confused "added fats" with "total fat". While total fat intake has remained stable over this time period, added fats have increased by 59%. The increase is almost exclusively due to industrially processed seed oils (butter and lard have decreased). Total fat has remained the same because we now eat low-fat cuts of meat and low-fat dairy products to make up for it! Another problem with the article is it only shows percent changes in consumption of different foods, rather than absolute amounts. This obscures some really meaningful information. For example, grain consumption is up a whopping 42%. That is the largest single food group change if you exclude the misinterpreted fat data. Corn is up 188%, rice 170%, wheat 21%. But in absolute amounts, the increase in wheat consumption is larger than corn or rice! That's because baseline wheat consumption dwarfed corn and rice. We don't get that information from the data presented in the article, due to the format. So now that I've deconstructed the data, let's see what the three biggest changes in the American diet from 1970 to 2006 actually are:- We're eating more grains, especially white wheat flour
- We're eating more added sweeteners, especially high-fructose corn syrup
- Animal fats from milk and meat have been replaced by processed seed oils
Wheat + sugar + processed vegetable oil = fat and unhealthy. Sounds familiar, doesn't it?
If paleolithic people were healthier than us due to their hunter-gatherer lifestyle, why did they have a shorter life expectancy than we do today? I was just reminded by Scott over at Modern Forager about some data on paleolithic (pre-agriculture) vs. neolithic (post-agriculture) life expectancy and growth characteristics. Here's a link to the table, which is derived from an article in the text Paleopathology at the Origins of Agriculture. The reason the table is so interesting is it allows us to ask the right question. Instead of "why did paleolithic people have a shorter life expectancy than we do today?", we should ask "how did the life expectancy of paleolithic people compare to that of pre-industrial neolithic people?" That's what will allow us to tease the effects of lifestyle apart from the effects of modern medicine. The data come from age estimates of skeletons from various archaeological sites representing a variety of time periods in the Mediterranean region. Paleolithic skeletons indicated a life expectancy of 35.4 years for men and 30.0 years for women, which includes a high rate of infant mortality. This is consistent with data from the Inuit that I posted a while back (life expectancy excluding infant mortality = 43.5 years). With modest fluctuations, the life expectancy of humans in this Mediterranean region remained similar from paleolithic times until the last century. I suspect the paleolithic people died most often from warfare, accidents and infectious disease, while the neolithic people died mostly from chronic disease, and infectious diseases that evolved along with the domestication of animals (zoonotic diseases). But I'm just speculating based on what I know about modern populations, so you can take that at face value.The most interesting part of the table is actually not the life expectancy data. It also contains numbers for average stature and pelvic inlet depth. These are both markers of nutritional status during development. Pelvic inlet depth is a measure of the size of the pelvic canal through which a baby would pass during birth. It can be measured in men and women, but obviously its implications for birth only apply to women. As you can see in the table, stature and pelvic inlet depth declined quite a bit with the adoption of agriculture, and still have not reached paleolithic levels to this day. The idea that a grain-based diet interferes with normal skeletal development isn't new. It's well-accepted in the field of archaeology that the adoption of grains coincided with a shortening of stature, thinner bones and crooked, cavity-ridden teeth. This fact is so well accepted that these sorts of skeletal changes are sometimes used as evidence that grains were adopted in a particular region historically. Weston Price saw similar changes in the populations he studied, as they transitioned from traditional diets to processed-food diets rich in white wheat flour, sweets and other processed foods. The change in pelvic inlet depth is also very telling. Modern childbirth is so difficult, it makes you wonder why our bodies have evolved to make it so drawn-out and lethal. Without the aid of modern medicine, many of the women who now get C-sections and other birth interventions would not make it. My feeling is that we didn't evolve to make childbirth so lethal. It's more difficult in modern times, at least partially because we have a narrower pelvic inlet than our ancestors. Another thing Weston Price commented on was the relative ease of childbirth in many of the traditional societies he visited. Here's an exerpt from Nutrition and Physical Degeneration:A similar impressive comment was made to me by Dr. Romig, the superintendent of the government hospital for Eskimos and Indians at Anchorage, Alaska. He stated that in his thirty-six years among the Eskimos, he had never been able to arrive in time to see a normal birth by a primitive Eskimo woman. But conditions have changed materially with the new generation of Eskimo girls, born after their parents began to use foods of modern civilization. Many of them are carried to his hospital after they had been in labor for several days. One Eskimo woman who had married twice, her last husband being a white man, reported to Dr. Romig and myself that she had given birth to twenty-six children and that several of them had been born during the night and that she had not bothered to waken her husband, but had introduced him to the new baby in the morning.
Now that's what I call fertility!
If paleolithic people were healthier than us due to their hunter-gatherer lifestyle, why did they have a shorter life expectancy than we do today? I was just reminded by Scott over at Modern Forager about some data on paleolithic (pre-agriculture) vs. neolithic (post-agriculture) life expectancy and growth characteristics. Here's a link to the table, which is derived from an article in the text Paleopathology at the Origins of Agriculture. The reason the table is so interesting is it allows us to ask the right question. Instead of "why did paleolithic people have a shorter life expectancy than we do today?", we should ask "how did the life expectancy of paleolithic people compare to that of pre-industrial neolithic people?" That's what will allow us to tease the effects of lifestyle apart from the effects of modern medicine. The data come from age estimates of skeletons from various archaeological sites representing a variety of time periods in the Mediterranean region. Paleolithic skeletons indicated a life expectancy of 35.4 years for men and 30.0 years for women, which includes a high rate of infant mortality. This is consistent with data from the Inuit that I posted a while back (life expectancy excluding infant mortality = 43.5 years). With modest fluctuations, the life expectancy of humans in this Mediterranean region remained similar from paleolithic times until the last century. I suspect the paleolithic people died most often from warfare, accidents and infectious disease, while the neolithic people died mostly from chronic disease, and infectious diseases that evolved along with the domestication of animals (zoonotic diseases). But I'm just speculating based on what I know about modern populations, so you can take that at face value.The most interesting part of the table is actually not the life expectancy data. It also contains numbers for average stature and pelvic inlet depth. These are both markers of nutritional status during development. Pelvic inlet depth is a measure of the size of the pelvic canal through which a baby would pass during birth. It can be measured in men and women, but obviously its implications for birth only apply to women. As you can see in the table, stature and pelvic inlet depth declined quite a bit with the adoption of agriculture, and still have not reached paleolithic levels to this day. The idea that a grain-based diet interferes with normal skeletal development isn't new. It's well-accepted in the field of archaeology that the adoption of grains coincided with a shortening of stature, thinner bones and crooked, cavity-ridden teeth. This fact is so well accepted that these sorts of skeletal changes are sometimes used as evidence that grains were adopted in a particular region historically. Weston Price saw similar changes in the populations he studied, as they transitioned from traditional diets to processed-food diets rich in white wheat flour, sweets and other processed foods. The change in pelvic inlet depth is also very telling. Modern childbirth is so difficult, it makes you wonder why our bodies have evolved to make it so drawn-out and lethal. Without the aid of modern medicine, many of the women who now get C-sections and other birth interventions would not make it. My feeling is that we didn't evolve to make childbirth so lethal. It's more difficult in modern times, at least partially because we have a narrower pelvic inlet than our ancestors. Another thing Weston Price commented on was the relative ease of childbirth in many of the traditional societies he visited. Here's an exerpt from Nutrition and Physical Degeneration:A similar impressive comment was made to me by Dr. Romig, the superintendent of the government hospital for Eskimos and Indians at Anchorage, Alaska. He stated that in his thirty-six years among the Eskimos, he had never been able to arrive in time to see a normal birth by a primitive Eskimo woman. But conditions have changed materially with the new generation of Eskimo girls, born after their parents began to use foods of modern civilization. Many of them are carried to his hospital after they had been in labor for several days. One Eskimo woman who had married twice, her last husband being a white man, reported to Dr. Romig and myself that she had given birth to twenty-six children and that several of them had been born during the night and that she had not bothered to waken her husband, but had introduced him to the new baby in the morning.
Now that's what I call fertility!
Like 99.9% of the world's population, I am mostly dependent on agriculture for my food. It's fun to pretend sometimes though. I enjoy foraging for berries, mushrooms and nuts.Last week, I went crabbing in the San Juan islands. We caught our limit of meaty dungeness crabs every day we put the pots out. If we had been working harder at it (and it was legal), we could easily have caught enough crabs to feed ourselves completely. We cooked them fresh and ate some the same day. We extracted the meat from the rest, and made an amazing crab bisque using a stock made from the shells, and lots of cream.Here's a "hunting photo". No smiling allowed; I had to look tough...
